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Prospects for biodiversity conservation:

Lessons from Atlantic Forest

Marcelo Tabarelli

UFPE

www.ufpe.br/ecoplan/

Talk content

Major findings from the Atlantic Forest research;

Forest response to human disturbances;

Forces modulating forest response;

Prospect for biodiversity in human-modified

landscapes;

Implications for conservation and research

agenda.

Finding 1: Biodiversity is not distributed

randomly

Altitudinal distribution

Tabarelli et al. 2010 Biological Conservation

Finding 2: Habitat loss is highly deterministic

Habitat loss

Tabarelli et al. 2010 Biological Conservation

Finding 3: Habitat protection is biased

Distribution of forest protection effort

Tabarelli et al. 2010 Biological Conservation

Finding 4: Human disturbances drive tropical

forests to hyper-fragmented landscapes

Intact forest

landscapes

Human-modified

Hyper-fragmented landscapes

(HML)

Forest cover and structural connectivity+ -

Human disturbances

Land-use intensification

Tabarelli et al. 2008 Biotropica

Finding 5: Disturbance-adapted species

proliferate in HML

0

20

40

60

80

100

Pioneer

species

Emergent

species

Canopy

species

Understory

species

Vertebrate

dispersed

species

Ecological groups

Perc

en

tag

e o

f tr

ee s

pecie

s

Forest edge

Forest interior

Source: Oliveira et al. 2004 Oryx

Proliferation of pioneer species on edge-affected habitats of Atlantic Forest

Proliferating species (winners!)

Birds

Reptiles

Non-flying mammals

Bats

Ants

8 col/ha

Urbas et al. 2007 JTE

Finding 6: Few biological strategies tend to

persist in HML

© Smithsonian Tropical Research Institute

Inconspicuous flowers, pollinated by

“diverse small insects” (DSI) are

more frequent in edge-affected

habitats and within pioneers

© Smithsonian Tropical Research Institute

© Smithsonian Tropical Research Institute

© Smithsonian Tropical Research Institute

Floral Type

Finding 7: Biological strategies typical of the

old-growth flora tend to disappear

Girão et al. 2007 PLoS One

Extirpation of sensitive tree functional groups

Non-inconspicuous/open flowers are

more frequent in forest interior plots and within old-growth flora

Brush flowers Tube flower

Flag flowersCamera flower

Floral Types

Tabarelli et al. (2010) Conservation Biology

Reproducitve strategies of tree species

Small fragments support…

50% of tree species richness;

30% of large-seeded species;

40% of shade-tolerant species;

25% of emergent tree species;

< 25% tree species pollinated by vertebrates.

Santos et al. 2008 Biol. Conserv.

Girão et al. 2007 PLoS One

Oliveira et al. 2008 Forest Ecol & Manag

Finding 8: Biological communities converge

at local and landscape scales

Floristic convergence among edge-affected habitats

Santos et al. Biol. Conserv. 2008

Forest interior plots

Edge

Second-growth

Fragment plots

Tree plot ordination based on reproductive trait abundance

Functional convergence among edge-affected habitats

individuals species

Lopes et al. Biol. Conserv. 2009

Forest interior plots

Edge

Second-growth

Fragment plots

ks

ja

ed

abc

g f

ha e

ab

e

Time after habitat fragmentation

e

b

ba

Convergence or biotic homogenization

Forest fragments

Pioneers proliferate

Old-growth flora collapses

Log10

Distance between pairs of subregions (Km)

1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8

Jacc

ard

's S

imila

rity

Ind

ex

0.10

0.15

0.20

0.25

0.30

0.35

Taxonomic similarity across sub-regions of Atlantic Forest

Lobo et al. (in press). Diversity and Distributions

20% increment on similarity

Pre 1980

Post 1980

Forest response to human-disturbances

Habitat Fragmentation

Edge

effectsFire Logging Hunting

Forest structural collapseElimination of frugivores

Pioneer

proliferation

Early-successional systems

Decline of shade-tolerant

trees

Source: Tabarelli et al. 2008 Biotropica

Creation of forest edges

Old-growth forest

Early-successional system

Secondarization of edge-affected habitats

Forces modulating secondarization

Time after initial disturbance

Early successional

Mid-successional

Old-growth stage

+

-

Forest response to human disturbances

Matrix harshness

Old-growth taxa favoring

Pioneer favoring

Time after initial disturbance

Early successional

Mid-successional

Old-growth stage

+

-

Environmental extremes

Forest response to human disturbances

Old-growth taxa favoring

Pioneer favoring

Time after initial disturbance

Early successional

Mid-successional

Old-growth stage

+

-

Collection of forest products

Old-growth taxa favoring

Pioneer favoring

Forest response to human disturbances

Time after initial disturbance

Early successional

Mid-successional

Old-growth stage

Historical exposure to disturbance

+

-

Forest response to human disturbances

Occurrence of disturbance-adapted species

Occurrence of disturbance-adapted species

Prospect for biodiversity-regulated

processes in human-modified landscapes

Time after disturbance

Sp

ec

ies

ric

hn

es

s

Fu

nc

tio

na

ld

ivers

ity

Bio

ma

ss

Pri

ma

ry p

rod

uc

tivit

y

Secondarization

Forest regeneration

Early succ. Mid-successional Late successional

Ecosystem functioning across forest regeneration/retrogressive succession

>90% < 50% < 30% < 10%

Intact FragmentedVariegated Relictual

Bio

div

ers

ity r

ete

ntion

+

-

Ecolo

gic

al serv

ices

Need f

or

managem

ent

Econom

ic v

alu

e o

f fo

rest

undisturbed

disturbed

Forest cover

Socia

l and c

ultura

l div

ers

ity

Land-use intensification

Landscape type

How much biodiversity is

expected to persist in the

Atlantic Forest?

It depends on..

Number of proliferating species;

Secondarization level experienced by the

remaining forest.

Prediction...

Few species will persist across

tropical human-modified

landscapes!!!!

(secondary-forest dwellers)

Tabarelli (2010) Biotropica

Theoretical implications for conservation

Any conservation strategy

that fails to safeguard

large blocks of core

primary forests has limited

potential for biodiversity

conservation, provision of

ecological services, and

long-term human well-

being based on forestry

activities.

Biodiversity Corridor Approach

Santos et al. (2008) Biological Conservation

Research Agenda

A promising approach

Human disturbances

Habitat loss and fragmentation;

Edge effects;

Disruption of species interactions

Over-exploitation;

Fire;

Climate change (climatic extremes).

Biodiversity-controlled

processes Ecological services;

Goods provision;

Conservation services;

Human cultural diversification;

Human well-being;

Human-society vulnerability to

global changes.

Secondarization Secondarization

shape shape

The big question!

To which extent do tropical forest approach

early-successional systems in response to

human disturbances?

By approaching such a system the negative

impacts on biodiversity-controlled processes

are inevitable and irreversible

Acknowledgements!

Collaborators

Dr Carlos A. Peres (UEA)

Dr Rainer Wirth (UK)

Dr Inara R Leal (UFPE)

Dr Ariadna F. Lopes (UFPE)

Ricardo Rodrigues (ESALQ)

Jean Paul Metzger (USP)

Lab team

Dr Felipe P Melo

MSc Severino R Pinto

MSc Antonio Aguiar

MSc Edgar Silva

MSc Waness Almeida

MSc Gabriel Mendes

Thanks for your attention !!!